Pulley drive system

ABSTRACT

A pulley drive system including a centrifugally governed two speed drive pulley assembly and a driven pulley assembly coactively connected by a belt. There is a speed selection mechanism which includes an auxiliary weight movable from a radially inward position to a radially outward position which in one position prevents the centrifugally governed two speed drive assembly from shifting and the auxiliary weight operation is actuated by a pivotal trigger which in turn is actuated by a control member movable in response to a control mechanism.

BACKGROUND OF THE INVENTION

1. Field of the Invention:

The present invention relates to a pulley drive system which iscentrifugally clutched and furthermore may act as a centrifugallygoverned two speed drive, the same centrifugal mechanism being utilizedfor both clutching and varying the pulley drive ratios.

2. Description of the Prior Art:

Variable speed pulley drive systems and centrifugally governed clutchesfor pulleys are well known in the prior art. For instance, U.S. Pat.Nos. 3,715,930; 3,771,378; 3,659,470; and 3,812,731 disclose suchvariable speed centrifugally operated drive pulleys.

It is known in the art to utilize a multiple-speed clutch which iscentrifugally controlled, such as the clutch disclosed in U.S. Pat. No.3,159,257 assigned to the same assignee as this invention. This type ofclutch has been used to vary the driven speed of mechanisms for clotheswashers. Trigger released auxiliary weights and a speed selectionmechanism to actuate the trigger for controlling the different speeds ofthese clutches is disclosed in U.S. Pat. No. 3,324,984, assigned to thesame assignee at this invention.

It is also known in the prior art to utilize a belt drive for operatingthe transmission of a clothes washing machine. An example of such a beltdrive is disclosed in U.S. Pat. No. 3,978,693 assigned to the sameassignee as the present invention. Automatic clothes washing machineshave at least two modes of operation, a washing mode and a spin mode.During the washing mode the vertical center post vaned structure oragitator is oscillated by means of a motor driven belt drive mechanismthrough a transmission. During the spin mode the agitator and basketcontaining the clothes are spun in unison at high speed to extractliquid from the clothes within the basket. In many cases it is desirableto provide two speeds of operation in these respective modes. In somecases this is obtained in the prior art by having the belt driventhrough a mechanism by a two speed motor and in others a two speedclutch mechanism is utilized. Such arrangements, however, are notentirely satisfactory.

By my invention I have improved the prior art pulley drive systems toprovide a means for clutching and obtaining a two speed drive systemparticularly useful in clothes washing machines which is simple inconstruction, of low cost, has good regulation, and provides torqueconversion to reduce the amount of energy used in obtaining the lowerspeed.

SUMMARY OF THE INVENTION

There is provided a pulley drive system particularly useful inconnection with automatic clothes washing machines. There is a drivemember, a drive pulley assembly on the drive member having a first halfpulley fixed to the drive member and a second half pulley rotatable withthe drive member and axially movable on the drive member relative to thefirst half pulley. There is also provided a collar rotatable with thedrive member and axially movable relative to the drive member andsecured to the second half pulley with a base member also secured to thedrive member and rotatable but not axially movable therewith. Betweenthe collar and base member is a spring whose opposite ends bear on thecollar and the base member, respectively. Flyweights are located betweenthe second half pulley and the base member such that during rotationthey exert centrifugal force on the second half pulley. There is adriven pulley assembly with a belt coactively connecting both the drivepulley assembly and the driven pulley assembly. An auxiliary weight ismounted on the base member for rotational movement therewith and movableby centrifugal force from a radially inward position to a radiallyoutward position relative to the drive member, the radially inwardposition engages the collar and the radially outward position disengagesthe collar.

A speed selection mechanism is provided and includes a trigger mountedon the base member and rotatable therewith, the trigger being pivotablefrom a first position radially outward of the drive shaft and engagingthe auxiliary weight to a second position disengaging the auxiliaryweight. A control member movable between first and second positions andmeans for so moving the control member is arranged so that the controlmember in its first position is remote from the rotary path of thetrigger and in its second position being in the rotary path of thetrigger only when the trigger is in its first position to thereby pivotthe trigger to its second position and allow the auxiliary weight to bedisengaged from said collar. Upon such disengagement the drive pulleyassembly operates to increase the diameter about which the driven belttravels thus providing for a second and faster belt speed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of a clothes washing machine whichincludes my invention, the view being partly broken away and partly insection to illustrate details.

FIG. 2 is a fragmentary side elevational view showing my centrifugaldrive pulley assembly in the slow belt driving mode, the mechanism beingpartly broken away partly in section to illustrate details.

FIG. 3 is a plan view taken along lines 3--3 of FIG. 2.

FIG. 4 is a fragmentary side elevational view of my centrifugal drivepulley assembly similar to FIG. 2 but showing the mechanism in the fastbelt driving mode, the mechanism being partly broken away and partly insection to illustrate details.

FIG. 5 is a plan view taken along lines 5--5 of FIG. 4.

FIG. 6 is a plan view of the pulley drive system embodying my invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to FIG. 1, I have shown therein an agitator-type clotheswashing machine 1 having a conventional basket or clothes receivingreceptacle 2 provided over its side and bottom walls with perforations 3and disposed within an outer imperforate tub or casing 4 which serves asa liquid receptacle. The basket 2 may be provided with a balance ring 6to help steady the basket when it is rotated at high speed.

Tub 4 is rigidly mounted within an appearance cabinet 7 which includes acover 8 hingedly mounted in the top portion 9 of the cabinet forproviding access to an opening 10 in the basket 2. As shown, a gasket 11may be provided so as to form a seal between the top of the tub 4 andthe portion 9 of the cabinet thereby to prevent escape of moisture andmoist air into the cabinet around the tub. The rigid mounting of tub 4within the cabinet 7 may be effected by any suitable means. As a typicalexample of one such means I have provided strap members 12, each ofwhich is secured at one end to an inturned flange 13 of the cabinet andat its other end to the outside of tub 4.

At the center of basket 2 there is positioned a vertical axis agitator14 which includes a centerpost 15 and a plurality of curved watercirculating means 16. Both the clothes basket 2 and the agitator 14 arerotatably mounted. The basket is mounted on a flange 18 of a rotatablehub 19 and the agitator 14 is mounted on a shaft (not shown) whichextends upwardly through the hub 19 and through the centerpost 15, andis secured to the agitator so as to drive it.

During a sequence of operations of machine 1, water is introduced intotub 4 and basket 2, agitator 14 is then oscillated back and forth on itsaxis, that is, in a horizontal plane within the basket, to wash theclothes therein. Then, after this washing step or period is completed,basket 2 and agitator 14 are rotated at high speed in unison to extractcentrifugally washing liquid from the clothes and discharge it to drain.Following this extraction operation a supply of clean liquid isintroduced into the basket for rinsing the clothes and the agitator isagain oscillated. Finally, the basket and agitator are once more rotatedat high speed to extract the rinse water. Basket 2 and agitator 14 maybe driven through any suitable means. By way of example, I have shownthem as driven from a reversible motor 20 through a system including atwo speed centrifugal drive pulley assembly 21 mounted from the motorshaft 64. This pulley assembly 21 will be described in detail later.Motor 20 is a single speed motor, and, in order to provide two differentspeeds of operation for agitator 14, the centrifugal pulley assembly 21is used. Depending upon the selection by the operator, the centrifugaldrive pulley assembly 21 is effective to drive a belt 25 at twodifferent speeds.

The two speed centrifugal pulley assembly 21 is controlled by means of aspeed selector solenoid 23. This solenoid operates a control mechanism22 which is effective in one position to condition the two speedcentrifugal pulley assembly 21 for the high speed drive of belt 25 andwhich, in the second position, is effective to condition the pulleyassembly 21 for the low speed drive of belt 25.

The belt 25 transmits power to a transmission assembly 24 and drivenpulley 26. Thus, depending upon the direction of motor shaft 64rotation, pulley 26 and transmission 24 are driven in oppositedirections. Transmission 24 is so arranged that it supports and drivesboth the agitator drive shaft and the basket mounting hub 19. When motor20 is rotated in one direction the transmission causes agitator 14 tooscillate in a substantially horizontal plane within the basket 2 at thespeed determined by centrifugal drive pulley assembly 21. Conversely,when the motor 20 is driven in the opposite direction the transmissionrotates wash basket 2 and agitator 14 together at a centrifuging speeddetermined by centrifugal drive pulley assembly 21 for centrifugalliquid extraction. While the specific type of transmission system useddoes not form part of my invention, reference is made to U.S. Pat. No.2,844,224 issued to James R. Hubbard et al on July 22, 1958 and owned bythe General Electric Company, assignee of the present invention. Thatpatent discloses in detail the structural characteristics of atransmission suitable for use in the illustrated machine.

In addition to operating transmission 24 as described, motor 20 alsoprovides a direct drive through a flexible coupling 27 to a pumpstructure, generally indicated at 28, which may include two separatepump units 29 and 30, both operated simultaneously in the same directionby motor 20. Pump unit 29 has an inlet which is connected by a conduit31 to an opening 32 formed at the lowermost point of tub 4. Pump unit 29also has an outlet which is connected by conduit 33 to a suitable drain(not shown). Pump unit 30 has an inlet connected by a conduit 34 to theinterior of tub 4 and outlet connected by a conduit 35 to a nozzle 36.The pumps are formed so that in the spin direction of motor rotationpump 29 will draw in liquid from opening 32 through conduit 31 anddischarge it through conduit 33 to drain, and in the other direction ofrotation pump 30 will draw in liquid through conduit 34 and discharge itthrough conduit 35 and nozzle 36, each of the pumps being substantiallyinoperative in the direction of rotation in which it is not used.

Nozzle 36 is positioned to discharge into a filter pan 37 secured on thetop of agitator 14 so as to be movable therewith. With this structurethen, when the motor is rotating so as to provide agitation, pump 30draws liquid through conduit 34 from tub 4 and discharges it throughconduit 35 so that the liquid passes from nozzle 36 into filter pan 37and then down through a number of small openings (not shown) provided inthe bottom 39 of filter pan and back into basket 2. In this manner, thefilter pan 37 with its small openings and its upstanding side wall 40causes lint which is separated from the clothes during a washingoperation to be filtered out of the water and thus prevented from beingredeposited on the clothes.

Motor 20, two speed centrifugal drive pulley assembly 21, transmission24, basket 2 and agitator 14 form a suspended washing and centrifugingsystem which is supported by the stationary structure of the machine soas to permit isolation of vibrations from the stationary structure. Itwill be understood that such vibrations occur primarily as a result ofhigh speed spinning of basket 2 with a load of clothes therein. Whileany suitable suspension structure may be used, one suitable structureincludes a bracket member 41 with transmission 24 mounted on top thereofand motor 20 mounted to the underside thereof. The bracket member inturn is secured to upwardly extending rigid members 42 and each of thetwo upwardly extending members 42 is connected to a cable 43 supportedfrom the top of the machine. While only a portion of the suspensionsystem is shown it is fully described in U.S. Pat. No. 2,987,190 issuedon June 6, 1961 to John Bochan and assigned to General Electric Company,assignee of the present invention.

In order to accommodate the movement which occurs between basket 2 andtub 4 without any danger of leakage between them the stationary tub 4 isjoined to the upper part of transmission 24 by a flexible member 44.Member 44 may be of any suitable configuration, many of which are knownin the art, to permit relative motion of the parts to which it is joinedwithout leakage therebetween.

Hot and cold water may be supplied to the machine through conduits 45and 46 which are adapted to be connected respectively to sources of hotand cold water (not shown). Conduits 45 and 46 are connected to aconventional mixing valve structure 47 having solenoids 48 and 49 sothat energization of solenoid 48 permits passage of hot water through avalve to a hose 50, energization of solenoid 49 permits the passage ofcold water through the valve, and energization of both solenoids permitsmixing of hot and cold water in the valve and passage of warm water intohose 50. Hose 50 has an outlet 51 positioned to discharge into basket 2so that when one or both of the solenoids 48 and 49 are energized, waterpasses into basket 2 and tub 4.

The level to which water rises in the basket and tub may be controlledby any suitable liquid level sensing means. One typical arrangement fordoing this is to provide an opening 52 in the side of tub 4 adjacent thebottom thereof, opening 52 being connected through a conduit 53 and atube 54 to a conventional pressure sensitive switch device 55 which maybe positioned within the control panel 56 of machine 1. In theconventional manner, water rises in basket 2 and tub 4 and exertsincreasing pressure on the column of air trapped in the tube 54, and ata predetermined pressure level the column of air then trips switch 55 toshut off whichever of solenoids 48 and 49 may be energized. The controlpanel 56 may have suitable manual controls, such as that shown at 57,extending therefrom so that the particular fabric cycle desired may becontrolled to effect the washing of different types of fabrics.

With reference to the FIGS. 2-5 particularly, the two-speed centrifugaldrive pulley assembly 21 will be described in detail. The belt 25 isdriven by a V-grooved pulley including a first half pulley 58 secured toa drive member such as motor shaft extension 60 by a key element 62 orany other suitable securing means. The first half pulley 58 is rotatablein unison with the motor shaft extension 60 which in turn is connectedto the motor shaft 64 of motor 20. The first half pulley 58 is notaxially movable on the drive shaft extension 60. The second half pulley66 is also secured to motor shaft extension 60 as by a key slot 68 suchthat the second half pulley 66 will rotate in unison with the driveshaft extension 60 and be axially movable on the drive shaft extension60. Below the second half pulley 66 there is a base member 70 which issecured to the drive shaft extension 60 again as by key means or slot 68but it is not axially movable relative to the drive shaft extension 60.Cavities 72 are provided between the second half pulley 66 and the basemember 70 to receive therein flyweights 74. The inner surface of thecavities 72 and the outer surface of the flyweights 74 havecomplementary slopes, the flyweights slope converging toward each otherin a direction radially outward of the drive shaft extension 60.

There is also provided below the base member 70 a collar 76 secured tothe drive shaft extension 60 for rotation in unison therewith andaxially movable relative to the drive shaft extension 60. The collar 76is secured to the second half pulley 66 by several mounting pins 78which pass through the oversize bores 80 in the base member 70 and aresecurely fastened to the second half pulley 66 as by threading means. Bythis arrangement then the second half pulley 66 and the collar 76 may beaxially movable relative to the motor shaft extension 60 while the basemember 70 remains in a fixed axial position relative to the motor shaftextension 60. A spring 82 surrounds the motor shaft extension 60 and hasone end 84 bearing against the upper surface 85 of the collar 76 and theopposite end 86 of the spring bears against the lower surface 88 of basemember 70.

The motor shaft extension 60 is secured to motor shaft 64 by a U bolt 90in cooperation with a bar 92 between the legs of the U bolt 90 engaginga flat area 94 on the shaft and secured thereagainst by nuts 96.

In cooperation with the drive pulley assembly 21 there is a speedselection mechanism which includes an auxiliary weight 98 located at oneside of the drive pulley assembly and radially outward of the motorshaft extension 60. The auxiliary weight 98 has a slot 100 therethroughand a nose 102 at one end thereof which, as shown in FIG. 2, engages thecollar 76 and the base member 70. Below the auxiliary weight 98 is atrigger 104 with both the trigger 104 and auxiliary weight 98 beingcarried by the base member 70 by means of a mounting pin 106 secured tothe base member 70 by thread means.

The trigger 104 is retained in its proper position by the mounting pin106 such that it will pivot thereabout. The trigger 104 has a dependingtang 108 and the auxiliary weight 98 has a depending tang 110, both ofwhich have biasing means such as spring 112 for the auxiliary weight 98and spring 114 for the trigger 104. Both springs 112 and 114 have theiropposite ends connected to a U shaped member 116 which is secured aroundthe U bolt 90. Springs 112 and 114 bias the auxiliary weight 98 andtrigger 104 respectively in a radially inward direction relative to themotor shaft extension 60.

A control mechanism 22 is utilized and includes a lever element 118which has at one end 120 a vertical arm 122. The opposite end 124 of thelever element 118 is positioned over the solenoid 23 so that whensolenoid 23 is actuated end 124 will be pulled down into contact withthe solenoid. The lever element 118 is centrally pivoted at point 126 bya pivot element 128. The end 120 of the lever element 118 is biased in adownward direction by a spring 130 so that end 124 will be out ofcontact with solenoid 24 when it is not actuated.

The operation of the drive pulley assembly and speed selection mechanismwill now be discussed. FIGS. 2 and 3 show the drive pulley assembly andspeed selection mechanism in the slow speed wherein the belt speed isthe slowest as it is driven by the smallest diameter formed between thefirst and second half pulleys. That is, the first half pulley 58 and thesecond half pulley 66 are spaced from each other so that the belt 25will ride in the V groove close to the motor shaft extension 60. Theflyweights 74 are prevented from moving the second half pulley 66upwardly by centrifugal force because the second half pulley 66 islocked in its position, as shown in FIG. 2, in axial relationship to themotor shaft extension 60. This locking is accomplished by mounting pins78 preventing axial movement of the second half pulley 66 by collar 76being in turn locked against axial movement by the nose 102 of auxiliaryweight 98 secured to base member 70. The auxiliary weight 98 isprevented from moving radially outward of the motor shaft extension 60by centrifugal force since trigger 104 is blocking such movement.

With reference to FIGS. 4 and 5, the second or fast belt speed isaccomplished by movement of the second half pulley 66 upwardly to abutthe first half pulley 58 thus increasing the V groove diameter aboutwhich the belt 25 is driven. With the increased diameter and the samemotor shaft speed the belt 25 will be accelerated accordingly. To obtainthe fast speed the speed selection mechanism is actuated as follows. Theelectronic control system, such as in a clothes washing machine, willenergize solenoid 23 at the proper preselected time in the operation ofthe machine thus drawing end 124 of lever element 118 downwardlyovercoming the bias force of spring 130 so that end 120 carryingvertical arm 122 is raised to the position shown in FIG. 4. Uponvertical arm 122 being raised the path of rotating trigger 104 isinterrupted and end 132 of trigger 104 hits the vertical arm 122 and indoing so is pivoted about mounting pin 106 to the position shown in FIG.5. At that time the end 134 of trigger 104 is disengaged from theauxiliary weight 98 thus allowing the centrifugal force to move theauxiliary weight 98 radially outward which in turn removes the nose 102thereof from engagement with the collar 76. With collar 76 now beingfree to move axially upward relative to the motor shaft extension 60 theflyweights 74 exert centrifugal force upon the second half pulley 66causing it to be moved upwardly and in abutting contact with the firsthalf pulley 58. The position of all of the aforementioned elementsremains as such until the motor 20 is de-energized and the centrifugalforce applied by the flyweights 74 and the auxiliary weight 98 areovercome by the respective springs 82, and 112. The trigger 104 isreturned to its position radially outward of the motor shaft extension60 by spring 114.

It should be noted in the mechanism arrangement described above that thecooperation between the fly weights 74 and both the second half pulley66 and base 70 is such that if the motor speed is reduced, as by a motoroverload or a low voltage condition, the spring 84 will overcome thebelow normal centrifugal force being applied by the fly weights 74 tothe second half pulley 66 and base 70 and the diameter of the drivepulley will be reduced automatically, increasing the mechanicaladvantage between drive pulley and driven pulley, and reducing motoroverload.

With reference particularly to FIG. 6 there is shown the driven pulley26 which in turn operates the transmission 24. The input powertransmission from the belt 25 is, as mentioned previously either a fastor slow speed depending upon the drive pulley assembly 21 and speedselection mechanism and its actuation by the controls of the clotheswashing machine. As the pulley diameter driving the belt 25 is varied,the belt 25 will either slacken or be tightened and this must becompensated for to provide effective operation of the pulley drivesystem. For this an idler assembly 136 is utilized and includes a roller138 that bears against the inner surface 139 of belt 25 and is free torotate about pivot pin 140 retained on pivot arm 142. The opposite endof pivot arm 142 is pivoted for movement by a pin 144. Pivot pin 144 isretained in a fixed location by attachment to a rigid structural member146. To place tension on the belt 25 by the roller 138 two springs 148and 150, respectively, are appropriately secured at one end 154 and 156,respectively, to a fixed support structure 152 and at the opposite ends158 and 160, respectively, to a roller bearing 162 about the pivot pin140.

To achieve proper belt tension in a given mechanism the location andbiasing force of springs 148 and 150 relative to the pivot pin 144 ofpivot arm 142 and the length of pivot arm 142 determines the forceapplied to the belt 25. The force applied to the belt 25 determines theamount of slippage around the first half pulley 58 and the second halfpulley 66 of the drive pulley assembly 21. As shown in FIG. 6, the belt25 and idler assembly 136 in solid line is when the mechanism is in highspeed spin and the dotted lines would be slow speed. The drive pulleyassembly 21 would be rotating counterclockwise in both cases. If thetorque between driven pulley 26 and the driving pulley assembly 21 risesabove normal the belt 25 tends to assume a straight line tangent to boththe driven and driving pulleys and roller 138 is moved opposite thespring bias force to provide belt slack and allow slight slippage of thebelt which acts as a clutching means.

In the agitation mode of machine operation the motor 20 is reversed sothe driving pulley assembly 21 would rotate clockwise as viewed in FIG.6. In this mode it is desirable to have full torque force and only asmall amount of roller 136 force against the belt is necessary to givesufficient belt tension to transmit high torque without belt slippage.It will be appreciated that other belt tensioning means may be used toaccomplish the belt tensioning function.

It should be apparent to those skilled in the art that the embodimentdescribed heretofore is considered to be the presently preferred form ofthis invention. In accordance with the patent statutes, changes may bemade in the disclosed apparatus and the manner in which it is usedwithout actually departing from the true spirit and scope of thisinvention.

What is claimed is:
 1. A two speed pulley drive system comprising:(a) adrive member, (b) a drive pulley assembly on said drive memberhaving;(i) a first half pulley fixed on the drive member, (ii) a secondhalf pulley rotatable with the drive member and axially movable on thedrive member relative to the first half pulley, (iii) a collar mountedconcentrically of and rotatable with the drive member, said collarhaving a bearing surface thereon and being axially movable relative tothe drive member and secured to the second half pulley, (iv) a basemember secured to the drive member and rotatable therewith, (v) a springhaving one end bearing on the collar and the other end bearing on thebase member, (vi) flyweights located between the second half pulley andthe base member, (c) a driven pulley assembly, (d) a belt coactivelyconnecting said pulley assemblies, (e) a speed selection mechanismincluding,(i) a single auxiliary weight mounted on the base member forrotational movement therewith and movable from a radially inwardposition to a radially outward position relative to the drive member,said radially inward position engaging a bearing surface of the collarand the radially outward position disengaged from the collar bearingsurface, (ii) a trigger mounted on the base member and rotatabletherewith, said trigger being pivotal radially outward of the drivemember from a first position in engagement with the auxiliary weight toa second position disengaging the auxiliary weight, (iii) a controlmember movable between first and second positions and means for somoving said control member, said control member in its first positionbeing remote from the rotary path of said trigger, said control memberin its second position being in the rotary path of said trigger onlywhen said trigger is in its first position to pivot said trigger to itssecond position and thereby allow said auxiliary weight to be disengagedfrom the bearing surface of said collar.
 2. The pulley drive system ofclaim 1 wherein there are means biasing said trigger and auxiliaryweight to a radially inward position.
 3. The pulley drive system ofclaim 1 wherein the control member is movable between first and secondpositions by a solenoid device.
 4. The pulley drive system of claim 1wherein the base member and collar are secured to the second half pulleyby common mounting pins.
 5. The pulley drive system of claim 1 whereinthe auxiliary weight has an elongated slot therethrough, and a mountingpin secured to the base member passes through the slot.
 6. The pulleydrive system of claim 5 wherein the trigger pivot is the mounting pinwith the auxiliary weight located between the trigger and base member.